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Puberal development of Clun Forest ram lambs in relation to time of birth

Published online by Cambridge University Press:  27 March 2009

Ó. R. Dýrmundsson  and
J. L. Lees
J. L. Lees
Affiliation:
Department of Agriculture, University College of Wales, Aberystwyth
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Summary

Some aspects of sexual development and the attainment of puberty in Clun Forest ram lambs were studied during the two seasons 1970–1. Strong correlations existed between parameters of penial, scrotal and testicular development. Sexual development in general appeared to be more closely associated with the body growth than the chronological age of the ram lamb.

Nevertheless, marked variation existed in both age and body weight at puberty. Although the majority of the lambs attained this stage of development at 4·5–5 months the age-range extended from 99 to 176 days. The mean body weight at puberty was 32·5 kg, ranging from 24·5 to 38·0 kg. There appeared to be an interaction between chronological age and general body development in relation to the appearance of sperm in the epididymides. Not only did it seem that a certain degree of body growth and testicular size was required before spermatozoa could be released, but also a limit of chronological age below which puberty was not attained. Large differences existed between individual lambs in both testicular and epididymal weights at puberty. There was a high degree of symmetry in growth between the left and the right testes and epididymides.

Time of birth influenced the pattern and rate of body growth and sexual development. This seemed to be largely due to seasonal fluctuations in nutritional conditions during rearing but the results obtained do not preclude the possibility that other seasonal factors, such as the daylight environment experienced by the ram lamb, might have a certain limited influence on sexual development.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 79 , Issue 1 , August 1972 , pp. 83 - 89
Copyright
Copyright © Cambridge University Press 1972

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References

Bibokski, J. (1967). Morphology of ram epididymis with special regard to the terminal part of the cauda epididymal duct. Ada biol. cracov. (Ser. Zool.) 10, 195–203.Google Scholar
Carmon, J. L. & Green, W. W. (1952). Histologioal study of the development of the testis of the ram. J. Anim. Sci. 11, 674–87.CrossRefGoogle Scholar
Colyer, R. J. (1971). Development of the testis and epididymis of the Clun Forest ram. J. agric. Sd., Camb. 76, 433–41.CrossRefGoogle Scholar
Courot, M. (1962). Développement du testioule chez l'agneau. Établissement de la spermatogenèse. Annls Biol. anim. Biochim. Biophys. 2 (1), 25–41.Google Scholar
Dun, R. B. (1955). Puberty in Merino rams. Aust. vet. J. 31, 104–6.CrossRefGoogle Scholar
Dýrmundsson, Ó. B. & Lees, J. L. (1972). A note on mating ability in Clun Forest ram lambs. Anim. Prod. 14, 259–62.Google Scholar
Johnstone, I. L. (1948). The growth and development of the penis in sheep: their possible relationship to posthitis. Aust. vet. J. 24, 86–8.Google Scholar
Land, B. B., Dickinson, A. G. & Read, J. L. (1969). The influence of seasonal variation on fertility and early body growth in sheep. Anim. Prod. 11, 251–7.Google Scholar
Lees, J. L. (1969). The reproductive pattern and performance of sheep. Outl. Agric. 6 (2), 82–8.Google Scholar
Louw, D. F. J. & Joubert, D. M. (1964). Puberty in the male Dorper sheep and Boer goat. S. Afr. J.agric. Sci. 7, 509–20.Google Scholar
Ortavant, B. (1956). Action de la duréee d'éeclairement sur les processus spermatogéenéetiques chez le béelier. C. r. Séeanc. Soc. Biol. 150, 471–4.Google Scholar
Ortavant, B. & Thibault, C. (1956). Influence de la duréee d'éeclairement sur les productions spermatiques du béelier. C. r. Séanc. Soc. Biol. 150, 358–61.Google Scholar
Pretorius, P. S. & Mabincowitz, G. (1968). Post-natal penis development, testes descent and puberty in Merino ram lambs on different planes of nutrition. S. Afr. J. agric. Sci. 11, 319–34.Google Scholar
Ragab, M. T., Sharafeldin, M. A. & Khalil, I. A. (1968). Sexual behaviour of male lambs as affected by the plane of nutrition. J. Anim. Prod. V.A.R. 6 (2), 89–94.Google Scholar
Skinner, J. D., Booth, W. D., Rowson, L. E. A. & Karg, H. (1968). The post-natal development of the reproductive tract of the Suffolk ram, and changes in the gonodotrophin content of the pituitary. J. Reprod. Fert. 16, 463–77.CrossRefGoogle Scholar
Skinner, J. D. & Rowson, L. E. A. (1968). Puberty in Suffolk and cross-bred rams. J. Reprod. Fert. 16, 479–88.CrossRefGoogle ScholarPubMed
Symington, R. B. (1961). Studies on the adaptability of three breeds of sheep to a tropical environment modified by altitude. VII. Sexual activity in relation to age of ram. J. agric. Sci., Camb. 56, 179–81.CrossRefGoogle Scholar
Watson, R. H., Sapsford, C. S. & McCance, I. (1956). The development of the testis, epididymis, and penis in the young Merino ram. Aust. J. agric. Res. 7, 574–90.CrossRefGoogle Scholar
Wiggins, E. L. & Terrill, C. E. (1953). Variation inpenis development in ram lambs. J. Anim. Sci. 12, 524–35.Google Scholar